its not safe. you need a dyno - you have no idea what you are doing to your air fuel ratios.
thats the opposite to most people.. usually you want to take a bit out of the top end (4000-7000) because the stock ECU runs a bit rich and when you up the boost/free the exhaust it runs even richer. normally its +'s at the low rpm's and -'s at the top end, but again, this will depend heavily on your exact modifications and engine setup.
icemm - there is no point in tuninig your AFC at all without a dyno. you wont get any increased performance without having it done properly on a dyno or at least with a wideband O2 sensor in the car. Leave it all at 0% until you can get it to a dyno - that big turbo will make it tricky to drive around on stock ECU, so keep it off boost till you can get it tuned.